beginner question : smil and frame

Hi

I'm using smil for a few hours only, so sorry for this very low-level 
question

I have 2 frames A and B. There is an object called "myniceobject" in the 
frame B, and I want to  link it to a enevenment defined in the frame A. 
Each frame has a specific name, but I'm unable to find the correct syntax 
to point to an object located in another frame

[frame A]
<smil:par begin="(????).myniceobject.click" fill="freeze" (??? missing 
arguments?)>

[frame B]
<img id="myniceobject">


Could someone help me please? There may be another approach, to define 
target frame or whatever, but i'm not skilled enough to see a solution.


benoit